h2g2 – The Guide to Life, The Universe and Everything is a site for collaborative writing published on the internet. It was founded in 1999 by Douglas Adams, the creator of the Hitchhiker's Guide to the Galaxy. Originally hosted independently, in 2001 it was taken over by the BBC, and thus shared the universal 'BBC ID' log-in. More recently, in 2011 the site was taken over by Not Panicking Ltd.

The site operates on a similar ethos to a wiki, whereby a community of editors create, edit and collaborate on a wide variety of articles. Many articles go through a formal peer review process,[1] and the premier articles become 'Approved Articles'. Because the site was hosted by the BBC for ten years, the tone of the articles have a British English methodology, but the subject matter is varied and represents a worldview.

In summary, think of h2g2 as something similar to say English Wikipedia, but without the bias, with maturity, and with a real community sense.